Surfacing apparatus



ocr. 14, 1930. H. 'R svn/11mm 1,778,470

' SURFACING APPARATUS Filed Nov`- 16, 1928 INVENTOR.

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ATTORNEYS Patented Oct. 14, 1930 UNITED STATES HERBERT R. Y STRATFOR-D,

OF CLEVELAND, OHIO, ASSIGNOR TO THE STBATHORE COMPANY, or CLEVELAND, Omo, A CORPORATION or OHIO SURFACING APPARATUS Application led November 16, 1928. Serial No. 819,820.

The present invention, relating, as indicated, to surfacing apparatus is more particularly directed to an improved supporting pad for use in surfacing apparatus of the type now so commonly used for grinding, polishing, buiing and similarly treating surfaces such as panels of wood, met-al and other material, and such articles as castings, automobile bodies, fenders, hoods and the/like.

lo lThe apparatus commonly employed for this purpose consists of a. frame or casing provided'witb handles for an operator and with -a projecting shaft, on the end of which is mounted a supporting pad, against which is removably secured a surfacing disk, usually constructed of abrasive adhesively secured to a suitable backing of paper, cloth or some combination of the two. The shaft on which the pad and disk are carried is operated ro through gearing journaled in the frame or casing and then by a exible shaft extending to a suitable source of power, although in many cases the operating shaft which carries the pad and disk are operated directly from a. self-contained air or electric motor mounted in the frame or casing.

rIhe present invention is directed to a new and improved pad to be used in machines of the above construction and for the purposes,

some of which are referred to above. The

principal object of the invention is the provision of a simple and inexpensive pad for the purpose described and one which has a more universal application and usefulness than the more specialized and expensive pads which have heretofore been employed, but

which have been better adapted to some individual type of surfacing operation than to general operations involving a considerable 0 range of operat-ions.

To the accomplishment of the foregoing and related ends, said invention, then, consists of the means hereinafter fully described and particularly pointed out in the claims; the annexed drawing and the following description setting forth in detail certain mechanism embodying the invention, such disclosed means constituting, however, but one of various mechanical forms in which the principle of the invention may be used.

In said annexed drawings Fig. 1 is a side elevation partially in section showing my improved supporting pad mounted in position upon a surfacing apparatus; Fig. 2 is a plan view of a pad; Fig. 3 is a similar view of a modification of the form of pad shown in Figs. l and 2; and Fig. 4 is a side elevation showing the use of my apparatus on a certain type of surface.

In Fig. 1 I have shown a. surfacing apparatus consisting of theframe or casing 1 provided with annularly related handles 2 and 3, of which the handle 3 is hollow and is adapted to receive therein a flexible shaft (not shown) for the operation of suitable connecting gears (not shown) mounted in a casing 1 and adapted to Operate a shaft 4 extending from the lower side of the casing. The shaft 4 is adapted to removably receive my improved supporting pad, which will now be described.

My improved pad consists of a. circular disk 10 formed of a suitable tough, compressible and iexible material so formed as to resist lexure, although permitting a considerable iiexing of the pad under heavy lateral pressure, thus adapting the pad to conform to such curved surfaces as are found in automobile bodies and similar constructions at such points as the fenders and around the cowl where the convex surfaces are employed. The pad may be formed of rubber, but of considerable stiffness and resistance to pressure. It is provided with a centrally disposed hub 11 which may be either secured to the pad proper by any suitable mechanical means or may be vulcanized thereto in the manner indicated. This hub 11 is provided with internal threading adapting it to removably engage over the extending threaded end of the shaft 4,. The pad is provided with a recessed portion 12 extending concentrically around its center for the reception lof a locking plate 13 which may be removed to retain in position against the lower or operating surface of the pad and abrasive disk or similar surfacing device 14. This abrasive disk 14 is provided with a central opening, through which passes a hub 15 formed as a part of the locking plate lso 13 and yen aging removably in suitable threading iigi the hollowed out end of the shaft 14.

In order to secure the desired resistance iiexibility can readilybe secured by properly relating the depth and thickness of thereinforcing ribs 16. `If desired reinforcing material may be introduced into the pad` but if so used this reinforcing material should not prevent bending and stretching of the lower portion of the pad as this is a require-l ment, as will be readily understood when the pad is bent through a4 considerable angle.

In Fig. 3 I have shown a modification of the construction previously described which consists in the use of radially extending ribs 20 in place of thevspirally arrangedandex'- tending ribs of the pad ofl Fig. 2, and it will be obvlous that various otherv similar modiiications may be employed, provided thatthe aggregate reinforcing given to the pad permits of vthe requisite fiexing under severe lateral pressure. Thepad must also 'have sufcient rigidity to cause the abrasive disk tive eration...

In a tended or a number of different operations and for use against different types of surfaces it is essential that the pad operate in as nearly'as ossible the same manner as relatively sti pads when used on fiat surfaces.

=If this actionis notsecured then the pad,

even on'flat surfaces, has to be applied to the work w1th conslderable pressure to produce to'operate effectively Awhen applied to a relai y flat surface Without the application i of excesspressure during this type of opad of the character described linone explained, change being made as regards fthe mechanism hereln disclosed, provided the.

means stated by any of the vfollowing claims or the e uivalent of such stated means be employe I therefore particularly point out and dis,- tinctl claim as my invention-:-

1. supportingpad of the character described comprisinga circular disk of tough flexure-resistant compressible material provided with a central opening and a hub member secured therein, said disk being provided with a series of reinforcing ribs extending from a point adjacent its outer periphery to said hub. o

2. A supporting pad of the character described comprising a circular Vdisk of tough flexure-resistant compressible material provided with a central opening and a hub member secured therein andh'aving a series of equidistantly spaced radially extending reinforcing ribs formed integral with said pad and projectingfrom its rearward surface,

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said ribs being adapted to progressively'support said pad against lateral flexure.

3. A supporting padof the character de-v scribed comprising a circular disk of tough exure-resistant compressible rubber provided vvith a central opening and a hub member secured therein, said disk being provided with a series of reinforcing ribs extending from a point adjacent its outer vperiphery to said hub.

Signed by me, this 10th day ofNovember,

HERBERT R. STRATFORD.

the desired cutting action, causing a considi arable flexing and a resultant severe Wear on the abrasive disk tending both to break the :backing of the disk and to loosen the grain of abrasive therefrom. The .present pad is well adapted to the varied service forv which it is intended. It has suicient rigidity to operate on flat surfaces without thel use of any considerable pressure and is still suiciently iexible to follow surfaces of considerable convexity when required and when the machine is applied to the surface with heavy pressure.-

Other modes of applying the principle of my invention may be employed instead of the lll 

